Bitmap auf Basis 64 Encode String

Question

Ich versuche, ein Bild in eine Bitmap zu konvertieren und sie dann in einem base64 string.I'm kodieren auf der Linie einen Null-Zeiger Ausnahme bekommen

bMap.compress(Bitmap.CompressFormat.PNG, COMPRESSION_QUALITY, 
      byteArrayBitmapStream); 

was falsch ist ? Beachten Sie, dass ich den Dateinamen mit dem Bild "pic2.jpg" in die unten stehende Methode eingabe.

unten ist mein Code:

private String convertToBitmap (String name){ 
    File imgFile = new File (name); 
    Bitmap bMap = BitmapFactory.decodeFile(imgFile.getAbsolutePath()); 
    final int COMPRESSION_QUALITY = 100; 
    String encodedImage; 
    ByteArrayOutputStream byteArrayBitmapStream = new ByteArrayOutputStream(); 
    bMap.compress(Bitmap.CompressFormat.PNG, COMPRESSION_QUALITY, 
      byteArrayBitmapStream); 
    byte[] b = byteArrayBitmapStream.toByteArray(); 
    encodedImage = Base64.encodeToString(b, Base64.DEFAULT); 
    return encodedImage; 
} 

unter meinem Log-Katze:

03-22 23:03:44.916 18331-18331/? I/art: Not late-enabling -Xcheck:jni (already on) 
03-22 23:03:44.916 18331-18331/? W/art: Unexpected CPU variant for X86 using defaults: x86 
03-22 23:03:45.029 18331-18331/com.example.reynaldo.getimageserver W/System: ClassLoader referenced unknown path: /data/app/com.example.reynaldo.getimageserver-2/lib/x86 
03-22 23:03:45.038 18331-18331/com.example.reynaldo.getimageserver I/InstantRun: Instant Run Runtime started. Android package is com.example.reynaldo.getimageserver, real application class is null. 
03-22 23:03:45.124 18331-18331/com.example.reynaldo.getimageserver W/System: ClassLoader referenced unknown path: /data/app/com.example.reynaldo.getimageserver-2/lib/x86 
03-22 23:03:45.372 18331-18331/com.example.reynaldo.getimageserver W/art: Before Android 4.1, method android.graphics.PorterDuffColorFilter android.support.graphics.drawable.VectorDrawableCompat.updateTintFilter(android.graphics.PorterDuffColorFilter, android.content.res.ColorStateList, android.graphics.PorterDuff$Mode) would have incorrectly overridden the package-private method in android.graphics.drawable.Drawable 
03-22 23:03:45.676 18331-18361/com.example.reynaldo.getimageserver D/NetworkSecurityConfig: No Network Security Config specified, using platform default 
03-22 23:03:45.865 18331-18367/com.example.reynaldo.getimageserver I/OpenGLRenderer: Initialized EGL, version 1.4 
03-22 23:03:45.865 18331-18367/com.example.reynaldo.getimageserver D/OpenGLRenderer: Swap behavior 1 
03-22 23:03:45.908 18331-18367/com.example.reynaldo.getimageserver E/EGL_emulation: tid 18367: eglSurfaceAttrib(1174): error 0x3009 (EGL_BAD_MATCH) 
03-22 23:03:45.909 18331-18367/com.example.reynaldo.getimageserver W/OpenGLRenderer: Failed to set EGL_SWAP_BEHAVIOR on surface 0xb493fe00, error=EGL_BAD_MATCH 

Answer 1

Versuchen Sie, diese

Bitmap bitmap = BitmapFactory.decodeResource(getResources(), R.drawable.image); // your pic2 
    ByteArrayOutputStream stream = new ByteArrayOutputStream(); 
    bitmap.compress(Bitmap.CompressFormat.PNG, 100, stream); 
    byte[] bitmapdata = stream.toByteArray(); 
    encodedImage = Base64.encodeToString(bitmapdata, Base64.DEFAULT); 
    return encodedImage; 

Answer 2

Bitmap bitmap = optimizePhoto(); 
ByteArrayOutputStream byteArrayOutputStream = new ByteArrayOutputStream(); 
bitmap.compress(Bitmap.CompressFormat.PNG, 100, byteArrayOutputStream); 
byte[] byteArray = byteArrayOutputStream.toByteArray(); 
Strng encoded = Base64.encodeToString(byteArray, Base64.DEFAULT); 

Wenn Sie Bild furthur

optimieren müssen

private Bitmap optimizePhoto() { 
     // Get the dimensions of the View 
     int targetW = 300; 
     int targetH = 300; 

     // Get the dimensions of the bitmap 
     BitmapFactory.Options bmOptions = new BitmapFactory.Options(); 
     bmOptions.inJustDecodeBounds = true; 
     BitmapFactory.decodeFile(getArguments().getString("imagePath"), bmOptions); 
     int photoW = bmOptions.outWidth; 
     int photoH = bmOptions.outHeight; 

     // Determine how much to scale down the image 
     int scaleFactor = Math.min(photoW/targetW, photoH/targetH); 

     // Decode the image file into a Bitmap sized to fill the View 
     bmOptions.inJustDecodeBounds = false; 
     bmOptions.inSampleSize = scaleFactor; 
     bmOptions.inPurgeable = true; 

     Bitmap bitmap = BitmapFactory.decodeFile(getArguments().getString("imagePath"), bmOptions); 

     return bitmap; 
    } 

Answer 3

Sie sollten dies versuchen:

private String convertToBitmap (String name){ 
      File imgFile = new File (name); 
      Bitmap bMap = BitmapFactory.decodeFile(imgFile.getAbsolutePath()); 
      if (bMap != null) { 
        bMap = Bitmap.createScaledBitmap(bMap, 256, 256, true); 
      String encodedImage; 
      ByteArrayOutputStream byteArrayBitmapStream = new ByteArrayOutputStream(); 
      bm.compress(Bitmap.CompressFormat.JPEG, 100, byteArrayBitmapStream); 
      byte[] b = byteArrayBitmapStream.toByteArray(); 
      encodedImage = Base64.encodeToString(b, Base64.DEFAULT); 
      StringBuilder sb = new StringBuilder(); 

      sb.append(encodedImage); 
      encodeString = sb.toString(); 
      return encodedImage; 
     } 
}